CVE-2024-3661: Openvpn · DHCP can add routes to a client’s routing table via the classless static route option (121)
Affects openvpnSource GCVE Database
Not known to be exploited · CVSS 7.6 High.
Data as of 13 Nov 2026, 13:11 UTC
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 6 May 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSconnmanpkg:deb/ubuntu/connman?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSgolang-github-apparentlymart-go-openvpn-mgmtpkg:deb/ubuntu/golang-github-apparentlymart-go-openvpn-mgmt?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlibreswanpkg:deb/ubuntu/libreswan?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSn2npkg:deb/ubuntu/n2n?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSnetwork-manager-fortisslvpnpkg:deb/ubuntu/network-manager-fortisslvpn?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSnetwork-manager-iodinepkg:deb/ubuntu/network-manager-iodine?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, users should be cautious about DHCP configurations and consider additional network segmentation or monitoring to detect unusual routing behavior.
Description
A vulnerability in OpenVPN allows DHCP to add routes to a client's routing table via the classless static route option (121). This can cause VPN-based security solutions to leak traffic over the physical interface, potentially exposing protected traffic to attackers on the same local network.
References
- ubuntu.com/security/CVE-2024-3661 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2024-3661 (opens in a new tab)
- datatracker.ietf.org/doc/html/rfc2131 (opens in a new tab)
- datatracker.ietf.org/doc/html/rfc3442 (opens in a new tab)
- tunnelvisionbug.com (opens in a new tab)
- leviathansecurity.com/research/tunnelvision (opens in a new tab)
- news.ycombinator.com/item?id=40279632 (opens in a new tab)
- arstechnica.com/security/2024/05/novel-attack-against-virtually-all-vpn-apps-neuters-their-entire-purpose/ (opens in a new tab)
- krebsonsecurity.com/2024/05/why-your-vpn-may-not-be-as-secure-as-it-claims/ (opens in a new tab)
- issuetracker.google.com/issues/263721377 (opens in a new tab)
- mullvad.net/en/blog/evaluating-the-impact-of-tunnelvision (opens in a new tab)
- zscaler.com/blogs/security-research/cve-2024-3661-k-tunnelvision-exposes-vpn-bypass-vulnerability (opens in a new tab)
- lowendtalk.com/discussion/188857/a-rogue-dhcp-server-within-your-network-can-and-will-hijack-your-vpn-traffic (opens in a new tab)
- news.ycombinator.com/item?id=40284111 (opens in a new tab)
- agwa.name/blog/post/hardening_openvpn_for_def_con (opens in a new tab)